A college professor’s simplified algorithm for drowsy-driver alerts could allow more automakers to offer the safety feature at a lesser cost.

Hans Van Dongen, who conducts sleep studies at Washington State University, has patented a new method for detecting driver fatigue. In principle, it’s very similar to Mercedes-Benz Attention Assist (standard on most of the company’s lineup) and BMW Attention Assistant (standard only on the 6- and 7-series and unavailable elsewhere), which are primarily steering-based and do not rely on lane-tracking cameras. But while those two systems assess dozens of other factors to confirm a driver’s drowsiness—including engine speed, use of the instrument panel, and time behind the wheel—before sounding an alarm to suggest the driver take a rest, the WSU version claims to be just as accurate by only recording steering movements and then calculating them against known patterns of lane drifting and sudden corrections, which are considered to be the most obvious signs that a driver is dozing off.

Van Dongen said his system would require cheap parts, such as a steering-wheel angle sensor he estimates at five dollars and a small chipset for data processing, which could possibly be installed by an aftermarket shop. While we’re certain it’d be more complex and expensive to install than Van Dongen suggests in his research paper—especially since it would require a separate interface to display the alerts and integration into a car’s existing electronics—automakers interested in spreading the technology might want to look into verifying his claims.

So far, only five automakers offer drowsy-driver detection systems, and all of them are restricted to models costing more than $30,000 or are bundled in pricey option packages. Van Dongen, as Mercedes-Benz has already done, is quick to point out the disadvantages of camera-based systems such as those used by Volvo and Ford since they’re inherently costlier and can’t work without clear lane markings (i.e., poor weather can render the system useless). Price is a serious obstacle, too. Ford, for example, restricts its Driver Alert feature to specific Fusion trims and requires $4350 in engine upgrades and option packages on the Fusion SE. Lexus uses an infrared camera mounted on the steering column to track a driver’s eye movements, but having the feature requires nearly $20,000 in additional options on the already pricey LS460.